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101.
We analyze self-reported anthropometric data pertaining to 2140 adults who emigrated to the United States, mainly from southern Italy, between 1908-1928 and 1960-1970. The mean height of immigrant men was 165.5 cm: they were taller than contemporary southern Italian men by 0.5-7.3 cm in different periods. The mean height of the Italian immigrant women born before 1952 was 157.6 cm, less than the national average. At the end of the 1990s, national women average height was 162 cm, 159.5 cm for southern women. There were age-related increases of weight and BMI: overweight was more prevalent in the 40-49 years age category. In the male sample, the mean values of BMI were within the overweight range in all age classes. The prevalence of obesity was higher in the male sample than among US men, whereas it was virtually identical in the women's sample and much higher than the values reported for several European countries for the period 1970-1980. 相似文献
102.
Chiara Giommarelli Alessandro Corti Rosanna Supino Enrica Favini Aldo Paolicchi Alfonso Pompella Franco Zunino 《Free radical biology & medicine》2009,46(11):1516-1526
The cell ability of tumor cells to tolerate stress conditions is a typical feature of solid tumors. In particular, the resistance to oxidative stress of melanoma cells likely contributes to their intrinsic drug resistance. In an attempt to develop novel strategies for overcoming the mechanisms of cellular protection against oxidative stress, in this study we have explored the efficacy of the combination of two prooxidant agents in two human melanoma cell clones. The selected clones are characterized by a marked difference in expression of γ-glutamyltransferase, which is known to produce a persistent low level of oxidative stress resulting in the stimulation of protective systems. The γ-glutamyltransferase-overexpressing clone exhibited a low susceptibility to arsenic trioxide-induced apoptosis, associated with low reactive oxygen species induction and increased catalase activity. The combination of arsenic trioxide with subtoxic concentrations of ascorbic acid resulted in a sensitization to apoptotic cell death. The expression of protective mechanisms, in particular catalase activity, accounted for the behavior of the resistant clone. The sensitization achieved by the combination was associated with a cellular response involving the ASK1/p38 axis, which is implicated in the regulation of catalase expression and the activation of apoptotic signals. In conclusion, the results of our study provide evidence that a rational combination of prooxidant agents may be effective in overcoming cellular tolerance to oxidative stress. 相似文献
103.
Eugenio Galano Erika Mangiapane Juliusz Bianga Angelo Palmese Enrica Pessione Joanna Szpunar Ryszard Lobinski Angela Amoresano 《Molecular & cellular proteomics : MCP》2013,12(8):2196-2204
An analytical approach was developed to study the incorporation of selenium (Se), an important trace element involved in the protection of cells from oxidative stress, into the well-known probiotic Lactobacillus reuteri Lb2 BM-DSM 16143. The analyses revealed that about half of the internalized Se was covalently incorporated into soluble proteins. Se-enriched proteins were detected in 2D gels by laser ablation inductively coupled plasma mass spectrometry imaging (LA-ICP MSI) and identified by capillary HPLC with the parallel ICP MS (78Se) and electrospray Orbitrap MS/MS detection. On the basis of the identification of 10 richest in selenium proteins, it was demonstrated that selenium was incorporated by the strain exclusively as selenocysteine. Also, the exact location of selenocysteine within the primary sequence was determined. This finding is in a striking contrast to another common nutraceutical, Se-enriched yeast, which incorporates Se principally as selenomethionine.In recent years selenium (Se)1 has received considerable attention as an essential element for human health. Severe Se deficiency is linked to oxidative stress and aging (1), elevated mortality with HIV (2), and irreversible brain injury (seizures, Parkinson''s disease) (3). Se occurs in nature principally in four inorganic chemical forms: the highly toxic selenide (Se2−−) (4), the moderately toxic selenate (SeO42−−) and selenite (SeO32−−), and elemental selenium (Se0) which is essentially nontoxic and can be stored by several bacterial species as nanoparticles on the cell surface (5, 6, 7). Inorganic selenium can be converted by biological systems (microorganisms, plants, and mammals) into seleno-amino acids, which are then incorporated into proteins. The two most common seleno-amino acids are selenomethionine (SeMet) and selenocysteine (SeCys). The former is synthesized via a route similar to the sulfur metabolic pathway in which selenium substitutes sulfur with no alteration of the protein structure (8, 9). The insertion of SeCys is genetically encoded by the UGA (TGA) codon and requires a SECIS element downstream of such a codon, a specific tRNA[Ser]Sec and accessory proteins (10).Selenoproteins containing genetically encoded SeCys are known to be synthesized by several bacteria. Among Gram-negative ones, E. coli produces three forms of selenated formate dehydrogenase (FdhN, FdhO, FdhH) (11). Among Gram-positive bacteria, all the selenoproteins experimentally known were found exclusively in anaerobic bacteria belonging to the clostridial clade. Examples include glycine reductase from Clostridium sticklandii (12) and Eubacterium acidaminophilum (13), proline reductase in C. sticklandii (14), xanthine dehydrogenase in C. acidiurici (15), and several antioxidant defense proteins (16). Enterococcus faecalis is the only member of the Firmicutes/Lactobacillales subdivision containing a SeCys-decoding trait (SelD) (17).Lactobacillus reuteri species has been widely described as a probiotic: it produces antimicrobial compounds, such as reuterin, with a broad spectrum of action (18), it is effective against diarrhea in children (19) and possesses immunomodulatory (potent TNF-inhibitory activity) effects in humans (20). Because L. reuteri species are native inhabitants of human microbiota, the association of the probiotic feature L. reuteri Lb2 BM-DSM 16143 with its ability to fix selenium into proteins, offers an innovative approach to combat human selenium deficiency.The objectives of this study were to investigate the ability of Firmicutes/Lactobacillales subdivision, Lactobacillus reuteri Lb2 BM-DSM 16143to incorporate selenium into proteins, and to investigate, for the first time, its speciation in order to identify the pathway(s) of this process (SeMet or SeCys). For this purpose an analytical approach based on laser ablation inductively coupled plasma mass spectrometry imaging (LA-ICP MSI) of Se-containing proteins in 2D gel electrophoresis, followed by their identification by capillary HPLC - electrospray Orbitrap MS/MS assisted by the quantitative control of selenium elution by ICP MS, was developed. 相似文献
104.
Alessandra Stefan Matteo Conti Diego Rubboli Lorenzo Ravagli Enrica Presta Alejandro Hochkoeppler 《Journal of biotechnology》2011,156(4):245
The expression of the recombinant diphtheria toxin mutant CRM197 in bacteria other than Corynebacterium diphtheriae has proven to be difficult. Here we propose a new and alternative procedure for the production of full-length CRM197 in Escherichia coli. The present study relates specifically to the expression of an artificial sequence and to a method for the isolation and purification of the corresponding protein. In particular, a synthetic gene coding for CRM197, bearing a short histidine tag and optimized for E. coli codon usage, was cloned in the pET9a vector. Accordingly, the over-expression of the protein was simply induced with arabinose in E. coli BL21AI. The recombinant protein was insoluble and always found inside protein aggregates, which were solubilised using urea. Surprisingly, the expression of CRM197, devoid of the short tag, always failed. Following a refolding step, the his-tagged CRM197 was purified by affinity and gel-filtration chromatography and the purity of the final preparation reached 95%. Interestingly, the recombinant protein features DNase activity, indicating that the presence of the tag is not affecting its biochemical properties. However, the removal of the synthetic tag could be easily obtained by incubating the target protein with a proper quantity of a commercial enterokinase. 相似文献
105.
Enrica Bianchi Monica Norcini†‡ Alan Smrcka§¶ Carla Ghelardini† 《Journal of neurochemistry》2009,111(1):171-180
Although alterations in μ-opioid receptor (μOR) signaling mediate excitatory effects of opiates in opioid tolerance, the molecular mechanism for the excitatory effect of acute low dose morphine, as it relates to μOR coupling, is presently unknown. A pronounced coupling of μOR to the α subunit of G inhibitory protein emerged in periaqueductal gray (PAG) from mice systemically administered with morphine at a dose producing acute thermal hyperalgesia. This coupling was abolished in presence of the selective μOR antagonist d -Phe–Cys–Tyr– d -Trp–Orn–Thr–Pen–Thr–NH2 administered at the PAG site, showing that the low dose morphine effect is triggered by μOR activated G inhibitory protein at supraspinal level. When Gβγ downstream signalling was blocked by intra-PAG co-administration of 2-(3,4,5-trihydroxy-6-oxoxanthen-9-yl)cyclohexane-1-carboxylic acid, a compound that inhibits Gβγ dimer-dependent signaling, a complete prevention of low dose morphine induced acute thermal hyperalgesia was obtained. Phospholipase C β3, an enzyme necessary to morphine hyperalgesia, was revealed to be associated with Gβγ in PAG. Although opioid administration induces a shift in μOR-G protein coupling from Gi to Gs after chronic administration, our data support that this condition is not realized in acute treatment providing evidence that a separate molecular mechanism underlies morphine induced acute excitatory effect. 相似文献
106.
Berniakovich I Trinei M Stendardo M Migliaccio E Minucci S Bernardi P Pelicci PG Giorgio M 《The Journal of biological chemistry》2008,283(49):34283-34293
Reactive oxygen species (ROS) and insulin signaling in the adipose tissue are critical determinants of aging and age-associated diseases. It is not clear, however, if they represent independent factors or they are mechanistically linked. We investigated the effects of ROS on insulin signaling using as model system the p66(Shc)-null mice. p66(Shc) is a redox enzyme that generates mitochondrial ROS and promotes aging in mammals. We report that insulin activates the redox enzyme activity of p66(Shc) specifically in adipocytes and that p66(Shc)-generated ROS regulate insulin signaling through multiple mechanisms, including AKT phosphorylation, Foxo localization, and regulation of selected insulin target genes. Deletion of p66(Shc) resulted in increased mitochondrial uncoupling and reduced triglyceride accumulation in adipocytes and in vivo increased metabolic rate and decreased fat mass and resistance to diet-induced obesity. In addition, p66(Shc-/-) mice showed impaired thermo-insulation. These findings demonstrate that p66(Shc)-generated ROS regulate the effect of insulin on the energetic metabolism in mice and suggest that intracellular oxidative stress might accelerate aging by favoring fat deposition and fat-related disorders. 相似文献
107.
Scaglioni S Veduci E Agostoni C Vergani B Stival G Riva E Giovannini M 《Prostaglandins, leukotrienes, and essential fatty acids》2004,71(2):91-95
The relationships between dietary habits and the blood fatty acid (FA) profile have been poorly explored, particularly in children. Aim of the present investigation was to look at the associations between dietary habits and the plasma pattern of FA in a school-age population. In 105 healthy 8-years old children, the nutritional habits have been evaluated by means of a Food Frequency Questionnaire and a 24-h recall. FA analyses (expressed as FA%) were performed by means of capillary gas chromatography. Statistics: non-parametric tests. The children with high pasta and low red meat consumption (n = 9), compared to those with either medium or low pasta and either high or medium red meat consumption (n = 96), showed lower levels of total saturated (29% vs. 35%, P = 0.001) and higher levels of total monounsaturated (30% vs. 24%, P = 0.04) FA in plasma. They also showed lower levels of LDL cholesterol (90 vs. 109 mg/dl, P = 0.08) and fasting insulin (4.0 vs. 6.3 microU/ml, P = 0.04) in blood. A high consumption of pasta coupled with a low intake of red meat may be marker of a food behaviour and/or lifestyle associated with a more favourable pattern of circulating FA and hematochemical metabolic markers. 相似文献
108.
Romeo S Dell'Agli M Parapini S Rizzi L Galli G Mondani M Sparatore A Taramelli D Bosisio E 《Bioorganic & medicinal chemistry letters》2004,14(11):2931-2934
Statine-based inhibitors of Plasmepsin II (PLMII) coupled with Primaquine have been designed using the 'double-drug' approach. The IC50 values for PLMII inhibition ranged from 0.59 to 400 nM and the best IC50 value for inhibition of Plasmodium falciparum growth in vitro was 0.4 microM, which represent a remarkable improvement compared to other statine-based PLMII inhibitors. 相似文献
109.
Traumatic lesions are commonly found in archaeological skeletal samples and provide useful information about various behavioral and cultural aspects of the populations. Our aim was to evaluate the relationship between the distribution and types of skeletal traumatic lesions and the different life-styles of past populations. We examined three necropolises in central Italy. Pozzilli (VI-IV century BC) and Quadrella (I-IV century AD) are from the same geographical area (Molise) but belong to different periods; Novilara (IX-VI century BC) is located in Marche but belongs to the Iron Age like Pozzilli. The lesions observed at Pozzilli seem not to be accidental, whereas the traumas observed at Quadrella can be attributed to occasional, unintentional events. Cranial injuries observed at Novilara strengthen the hypothesis that the population was composed, at least in part, of warriors. Our results suggest the presence of a relationship between skeletal traumatic lesions and life-styles of populations. 相似文献
110.